Conformal automobile FM radio receivers typically are formed in the front or rear window opening of the vehicle. These antennas are designed to provide good reception of signals within the FM broadcast band, 88 to 108 Mhz (3.5 to 2.8 meters wavelength).
Unfortunately, the front and rear window openings which are typically defined by the conductive vehicle body have resonances within the FM broadcast band, and these resonant openings create undesirable distortions from the omnidirectional antenna pattern desired.
It is a principal object of the present invention to reduce the adverse effects which would otherwise result from these undesired electromagnetic resonances.